HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Feb 24, 2010, 03:27 PM
sleep hard
vx99's Avatar
adelaide, south australia.
Joined Dec 2006
579 Posts
Help!
to hot glue or not to hot glue

hi guys,

i've built a couple of 40 -48" foamy planks for frontside flying, and used hot glue for the spars.

when building a JW/fat albert type plank (current project) for big frontside air and ds, is hot glue still a valid method? or is goop or epoxy for the spars a better bet for these types of planks and the likely abuse they'll receive?

thanks in advance, dave
vx99 is offline Find More Posts by vx99
Reply With Quote
Sign up now
to remove ads between posts
Old Feb 24, 2010, 04:06 PM
Pledged to Always Chase Wind
deputybuzz's Avatar
USA, UT, Salt Lake City
Joined Oct 2004
1,629 Posts
Epoxy, Goop or my new favorite, Gorilla Glue. Hot Glue won't penetrate the cells of foam like the others. The glue is too thick and cools down too fast. Resist temptation to use it for anything that can fly....IMO
deputybuzz is offline Find More Posts by deputybuzz
Last edited by deputybuzz; Feb 24, 2010 at 09:38 PM.
Reply With Quote
Old Feb 24, 2010, 04:45 PM
Registered User
KurtMc's Avatar
Sacramento, CA
Joined Sep 2003
1,154 Posts
Yeah, that Gorilla Glue CA (blue cap) is the shizz nizzle! I fixed the over-foot strap on a pair of busted foam Tevas with it last fall and they are still holding together, water and all. Best glue I've ever used.
KurtMc is offline Find More Posts by KurtMc
Reply With Quote
Old Feb 24, 2010, 05:19 PM
sleep hard
vx99's Avatar
adelaide, south australia.
Joined Dec 2006
579 Posts
Quote:
Originally Posted by deputybuzz View Post
The glue is too thick and cools down too fast. Resist temptation to use it for anything that can fly....IMO
thanks deputy; you're talking about hot glue here?
vx99 is offline Find More Posts by vx99
Last edited by vx99; Feb 24, 2010 at 05:25 PM.
Reply With Quote
Old Feb 24, 2010, 05:33 PM
TD- F3K- Slope - What to fly?
Dale Thompson's Avatar
Cupertino CA
Joined Aug 2005
1,507 Posts
Try the fast cure PU Gorilla Glue (It cures white). Spray a little mist of water on the parts before gluing them. Make sure the spars do not float up when the glue foams and fills the spar slot.

Try some on a small part and see how it foams.

Once it cures it's about the same consistancy as the foam core and can be cut and sanded to match the airfoil shape.
Dale Thompson is online now Find More Posts by Dale Thompson
Reply With Quote
Old Feb 24, 2010, 05:59 PM
sleep hard
vx99's Avatar
adelaide, south australia.
Joined Dec 2006
579 Posts
Quote:
Originally Posted by Indarotor View Post
Try the fast cure PU Gorilla Glue (It cures white). Spray a little mist of water on the parts before gluing them. Make sure the spars do not float up when the glue foams and fills the spar slot.

Try some on a small part and see how it foams.

Once it cures it's about the same consistancy as the foam core and can be cut and sanded to match the airfoil shape.
that sounds great indarotor; unfortunately we don't get gorilla glue here in oz.

anybody wanna send me some? happy to paypal etc...

dave
vx99 is offline Find More Posts by vx99
Reply With Quote
Old Feb 24, 2010, 06:19 PM
Pledged to Always Chase Wind
deputybuzz's Avatar
USA, UT, Salt Lake City
Joined Oct 2004
1,629 Posts
yes.... I was referring to the hot glue.

Epoxy is your best choice if you can't get gorilla. I love the flexibility and durability of goop but it shrinks when it dries and it is not easy to cut or sand it. It is a good idea to have all these glues. As you get to know them you will discover when and where to use them best.
deputybuzz is offline Find More Posts by deputybuzz
Reply With Quote
Old Feb 24, 2010, 08:20 PM
It flies!
Sean Moloney's Avatar
Sunshine Coast, Australia
Joined Jun 2007
1,538 Posts
Hey Dave, you should be able to find PU glue at Bunnings or most other hardware stores in Aus - either Vise Supergrip Polyurethane Glue or Selley's Aquadhere Durabond Polyurethane glue. I've tried thickened epoxy, goop, CA and PU for gluing in spars, and I reckon PU is the best of those four. You absolutely must weight or clamp the spars in place while the PU cures, or the foaming glue will push the spar out of its slot.
Sean Moloney is offline Find More Posts by Sean Moloney
Reply With Quote
Old Feb 24, 2010, 10:48 PM
sleep hard
vx99's Avatar
adelaide, south australia.
Joined Dec 2006
579 Posts
Quote:
Originally Posted by Sean Moloney View Post
Hey Dave, you should be able to find PU glue at Bunnings or most other hardware stores in Aus - either Vise Supergrip Polyurethane Glue or Selley's Aquadhere Durabond Polyurethane glue. I've tried thickened epoxy, goop, CA and PU for gluing in spars, and I reckon PU is the best of those four. You absolutely must weight or clamp the spars in place while the PU cures, or the foaming glue will push the spar out of its slot.
thanks for that sean, i'll go looking (again). i was looking for "gorilla" brand stuff, i guess, was what i meant when i said we couldn't get it here. i'll try the selleys or vise.

cheers!
vx99 is offline Find More Posts by vx99
Reply With Quote
Old Feb 25, 2010, 07:41 AM
Objects in mirror are losing
1000MPH's Avatar
USA, NV, Reno
Joined May 2003
3,586 Posts
It may depend on the hot glue. I know Jack Cooper uses it and I have used it with excellent results. Post mortems haven't revealed any more debonding than PU or epoxy. Maybe preprep is key, Wipe down EPP and spar with acetone.
I prefer the control and relative speed of white PU for spars but goop is the superior bond.
Another thing is I don't like to clamp anything that may have a springing action, like carbon spars. When it's all set and you release the pressure you may get warps. I spend a lot of time making sure spars drop fit with no pressure. Sorry to be devil's advocate, just some thing to keep in mind.
1000MPH is offline Find More Posts by 1000MPH
Reply With Quote
Old Feb 25, 2010, 08:45 AM
Put in all the lead
n-tropic's Avatar
Devon, UK
Joined Dec 2003
1,591 Posts
I like to use spread the bottom of the spar channel with Goop, fit the spar and let the Goop go off properly (at leat 24hrs depending on atmospheric conditions). Then use PU to fill in around the spar and fill the rest of the channel. It takes a bit longer but you get the benefit of Goop's superior strength and grip to the surface of the spar plus the filling capability and sandability of the PU.

Steve
n-tropic is offline Find More Posts by n-tropic
Reply With Quote
Old Feb 25, 2010, 10:53 AM
Pledged to Always Chase Wind
deputybuzz's Avatar
USA, UT, Salt Lake City
Joined Oct 2004
1,629 Posts
Steve....I like that idea. Nothing can top Goop. I will give that a try on my next build.

Stu...I am curious about the hot glue. For doing a quick and lite build I can see why you might use hot glue but how do you get the spar in place before the glue cools down? Seems like by the time you get your glue from one end to the other the end you started on won't be soft enough to push the spar in place? Also, Seems like hot glue would go solid before it can get worked into the foam cells. This would created a bond that is much easier to break away from the foam? Would it be best on a larger wood spars versus small carbon spars?
deputybuzz is offline Find More Posts by deputybuzz
Reply With Quote
Old Feb 25, 2010, 02:11 PM
Objects in mirror are losing
1000MPH's Avatar
USA, NV, Reno
Joined May 2003
3,586 Posts
Steve's method is the ultimate. For me, it also depends on the kind of spar. I would absolutely use goop on an internal tube spar and I use thin CA on ribbon spars. I use thinned goop on sub TE ribbon spars. On some spar installs, like a JW, when the wing is put back in the beds with wax paper, goop can be a pain as it won't cure for days. This is when I use white P/U.
Hot glue: I've used it on wood and square carbon. I would imagine wood is better.
You need a good gun and you need to work fast. I lay a bead on the bottom of the channel, install the spar and then stick the nozzle of the gun between the spar and the foam and squirt away. you can go over any excess with an iron.

still another method,
Vic (VV) uses CA every couple of inches to tack the spar in place while the glue cures.
1000MPH is offline Find More Posts by 1000MPH
Reply With Quote
Old Feb 25, 2010, 03:14 PM
Suspended Account
Joined May 2000
8,535 Posts
...
Arbo is offline Find More Posts by Arbo
Last edited by Arbo; Apr 13, 2010 at 12:18 AM.
Reply With Quote  (Disabled)
Old Feb 25, 2010, 07:13 PM
sleep hard
vx99's Avatar
adelaide, south australia.
Joined Dec 2006
579 Posts
more great info; thanks fellas.

sounds like the hardest thing i have to do now is select a method
vx99 is offline Find More Posts by vx99
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Pink FFF foam from home depot, alternate glue to hot glue? GreenAce92 Foamies (Scratchbuilt) 13 Dec 24, 2009 06:57 PM
Discussion CA, hot glue, or gorilla cgage The Builders Workshop 6 Dec 09, 2009 02:53 AM
Discussion to glue or not to glue that is the question mr2essions Beginner Training Area (Aircraft-Electric) 5 Jul 15, 2008 02:49 AM
Help! Glue or not to glue how should i attach the wings Powerhawkz Electric Plane Talk 5 Jul 02, 2007 09:51 PM
Discussion To Glue or Not To Glue? lowflyer Slope 6 Oct 22, 2003 12:19 PM